US6491725B1 - Keyhole button - Google Patents
Keyhole button Download PDFInfo
- Publication number
- US6491725B1 US6491725B1 US09/691,158 US69115800A US6491725B1 US 6491725 B1 US6491725 B1 US 6491725B1 US 69115800 A US69115800 A US 69115800A US 6491725 B1 US6491725 B1 US 6491725B1
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- US
- United States
- Prior art keywords
- keyhole
- brim portion
- keyhole button
- brim
- button
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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- 239000013589 supplement Substances 0.000 claims abstract description 4
- 239000001506 calcium phosphate Substances 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- 229910000389 calcium phosphate Inorganic materials 0.000 claims description 4
- -1 calcium phosphate compound Chemical class 0.000 claims description 4
- 235000011010 calcium phosphates Nutrition 0.000 claims description 4
- 230000002093 peripheral effect Effects 0.000 claims description 4
- 210000000988 bone and bone Anatomy 0.000 description 8
- 239000011148 porous material Substances 0.000 description 8
- 229910052588 hydroxylapatite Inorganic materials 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical compound [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 description 4
- 238000007428 craniotomy Methods 0.000 description 3
- 229920000609 methyl cellulose Polymers 0.000 description 3
- 239000001923 methylcellulose Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- XYJRXVWERLGGKC-UHFFFAOYSA-D pentacalcium;hydroxide;triphosphate Chemical compound [OH-].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O XYJRXVWERLGGKC-UHFFFAOYSA-D 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 230000008602 contraction Effects 0.000 description 2
- 210000003792 cranial nerve Anatomy 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 210000001951 dura mater Anatomy 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 238000001356 surgical procedure Methods 0.000 description 2
- 206010037660 Pyrexia Diseases 0.000 description 1
- 239000000316 bone substitute Substances 0.000 description 1
- YYRMJZQKEFZXMX-UHFFFAOYSA-L calcium bis(dihydrogenphosphate) Chemical compound [Ca+2].OP(O)([O-])=O.OP(O)([O-])=O YYRMJZQKEFZXMX-UHFFFAOYSA-L 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000006735 deficit Effects 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 210000002454 frontal bone Anatomy 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 229910000150 monocalcium phosphate Inorganic materials 0.000 description 1
- 235000019691 monocalcium phosphate Nutrition 0.000 description 1
- 230000003387 muscular Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011369 resultant mixture Substances 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 210000003582 temporal bone Anatomy 0.000 description 1
- 210000001519 tissue Anatomy 0.000 description 1
- 229910000391 tricalcium phosphate Inorganic materials 0.000 description 1
- 235000019731 tricalcium phosphate Nutrition 0.000 description 1
- 229940078499 tricalcium phosphate Drugs 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
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- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/688—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin for reattaching pieces of the skull
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/02—Prostheses implantable into the body
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F2002/30878—Special external or bone-contacting surface, e.g. coating for improving bone ingrowth applied in original prostheses, e.g. holes or grooves with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
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- A—HUMAN NECESSITIES
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- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
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- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
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- A—HUMAN NECESSITIES
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- A—HUMAN NECESSITIES
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- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
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- A—HUMAN NECESSITIES
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- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2310/00—Prostheses classified in A61F2/28 or A61F2/30 - A61F2/44 being constructed from or coated with a particular material
- A61F2310/00005—The prosthesis being constructed from a particular material
- A61F2310/00179—Ceramics or ceramic-like structures
- A61F2310/00293—Ceramics or ceramic-like structures containing a phosphorus-containing compound, e.g. apatite
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- Health & Medical Sciences (AREA)
- Orthopedic Medicine & Surgery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Veterinary Medicine (AREA)
- Public Health (AREA)
- General Health & Medical Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- Engineering & Computer Science (AREA)
- Neurosurgery (AREA)
- Heart & Thoracic Surgery (AREA)
- Chemical & Material Sciences (AREA)
- Transplantation (AREA)
- Surgery (AREA)
- Biomedical Technology (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Cardiology (AREA)
- Neurology (AREA)
- Molecular Biology (AREA)
- Vascular Medicine (AREA)
- Medical Informatics (AREA)
- Inorganic Chemistry (AREA)
- Dermatology (AREA)
- Medicinal Chemistry (AREA)
- Epidemiology (AREA)
- Prostheses (AREA)
- Surgical Instruments (AREA)
- Materials For Medical Uses (AREA)
Abstract
A keyhole button used as a supplement of a keyhole portion formed on a cranium is constituted to have a brim portion having front and back surfaces, and a shaft portion integrally provided on the back surface of the brim portion. The front surface of the brim portion is convexed in a first direction, and concaved in a second direction that is perpendicular to the first direction.
Description
The present invention relates to a keyhole button used as replenishment for a keyhole portion of a cranium formed when trepanation of the frontal or temporal bone is performed in the field of cranial nerve surgery. More particularly, the present invention relates to a keyhole button, which is superior in the adaptability to an organism, and in the stability, and does not disfigure the appearance of face after the operation is performed.
Conventionally, many craniotomy operations and closing operations have been performed in the field of cranial nerve surgery. Generally, a craniotomy operation includes following steps:
incising a head skin and exposing a cranium;
making some fossae on a cranium by a drill in accordance with a size and a region of the portion to be trepanned;
cutting between the fossae by a line saw;
taking out a bone flap; and
dissecting an internal dura mater.
In this operation, a portion at which a fossa is firstly made by drilling is located near the temple, and is called a “keyhole.”
The shape of the keyhole portion varies depending on the shape of the bone of individual patient and/or a doctor who performs the operation. Accordingly, it has been difficult to make a standard product of a bone substitute (which is referred to as a keyhole button). Conventionally, when the craniotomy has been performed, resin is filled into the keyhole portion as the supplemental member. However, there is a problem in adaptability to an organism and fever thereof. Recently, the keyhole buttons made of calcium phosphate compound, which has bio-compatibility, or adaptability to an organism, are used in some cases. However, such keyhole buttons have a stability problem and/or an appearance problem since the keyhole button does not match the shape around the keyhole portion.
It is therefore an object of the present invention to provide an improved keyhole button, which has high adaptability to an organism and stability, and further, with which the appearance of the face after the operation is performed is not disfigured.
For the above object, according to the present invention, there is provided a keyhole button used as a supplement of a keyhole portion formed on a cranium. The keyhole button is constituted to have a brim portion having front and back surfaces, and a shaft portion integrally provided on the back surface of said brim portion. The front surface of the brim portion is convexed in a first direction, and concaved in a second direction that is perpendicular to the first direction. Thus, the keyhole button functions as an excellent bone supplement in view of the adaptability to an organism, stability, and an appearance after the operation.
Preferably, the shaft portion is substantially cylindrical.
Further, the brim portion has a rounded-rectangular shape having longer axis and shorter axis, the longer axis extending in said first direction, the shorter axis extending in said second direction. Furthermore, the center of said shaft portion is shifted from the center of said brim portion in said first direction.
Still optionally, a peripheral portion on said front surface of said brim portion is beveled.
It is preferable that the keyhole button is made of porous calcium phosphate compound. In this case, it is preferable that the porosity of said keyhole button is 55% or less.
Further optionally, the keyhole button is formed of porous sinter material. Since the keyhole button is formed of the porous material, the brim portion can be shaped relatively easily by sintering, the thickness of the brim portion can be made relatively small.
FIG. 1A is a plan view of a keyhole button according to an embodiment of the present invention;
FIG. 1B is a side view of the keyhole button shown in FIG. 1A;
FIG. 2A is a cross-sectional view of the keyhole button taken along line A—A in FIG. 1A;
FIG. 2B is a cross-sectional view of the keyhole button taken along line B—B in FIG. 1A; and
FIG. 3 is a drawing schematically illustrating an inserted keyhole button.
Hereinafter, a keyhole button 1 according to an embodiment of the invention will be described with reference to the accompanying drawings.
FIG. 1A is a plan view of the keyhole button 1 according to an embodiment of the present invention. FIG. 1B is a side view of the keyhole button 1. FIG. 2A is a cross-sectional view of the keyhole button 1 taken along line A—A in FIG. 1A, and FIG. 2B is a cross-sectional view of the keyhole button 1 taken along line B—B in FIG. 1A. FIG. 3 is a drawing schematically illustrating an inserted keyhole button 1.
As shown in FIGS. 1A-2B, the keyhole button 1 according to the embodiment has integrally formed shaft portion 2 and brim portion 3, which are formed of porous sinter. Since the keyhole button 1 is formed of the porous material, the brim portion 3, which is slightly bent, can be formed relatively easily by sintering.
Considering the strength, it is desirable that the porosity of the porous sinter is 55% or less. The porosity is defined as a ratio of the volume of pores to the volume of entire material. Preferably, the porosity is 1%-15%, and more preferably, the porosity is 10%-15%. In view of the adaptability to an organism, it is desirable that the keyhole button 1 is made of calcium phosphate compound such as monocalcium phosphate, tricalcium phosphate, hydroxyapatite {Ca5(PO4)3OH}, or the like. In particular, the composition of hydroxyapatite is substantially the same as the inorganic content of an organismic bone. Accordingly, the hydroxyapatite has relatively high adaptability to an organism.
Next, the shape of the shaft portion 2 and the brim portion 3, and exemplary manufacturing methods of the keyhole button 1 will be described.
1. Brim Portion
As shown in FIG. 1A, since the brim portion 3 contacts the cranium and the muscular tissues on the upper layer of the cranium, it is desirable that the brim portion 3 has a rounded-rectangular shape. In this specification, the rounded-rectangular shape is defined as a combination of hemi-circular side portions and a rectangular portion therebetween.
In this specification, a direction along which the hemi-circular side portions and the rectangular portion are aligned is referred to as a first direction. Further, a line segment, which passes the center C1 of the rounded-rectangular shape and extends in the first direction, starting from one end to the other end of the brim portion, will be defined as a longer axis of the brim portion 3. Further, a direction, which is perpendicular to the first direction is referred to as the second direction, and a line segment extending from one end to the other end, in the second direction, of the brim portion 3 and passes the center C2 of the rounded-rectangular shape will be referred to as a shorter axis of the brim portion 3.
Because of the shape of the brim portion 3, which is symmetrical with respect to the longer axis thereof, the same keyhole button can be used for the either of right and left side keyhole portions. It is desirable that the ratio (W/L) of the length W of the shorter axis to the length L of the longer axis is, although it depends on the shape of the bone of a patient, within a range from 0.3 to 1, and more preferably from 0.4 to 0.8. Specifically, it is desirable that the brim portion 3 is formed such that the length W of the shorter axis thereof is within a range form 8 mm to 20 mm, and the length L of the longer axis is within a range of 8 mm to 30 mm, with maintaining the ratio W/L within the above range.
Besides the shape in the top view as described above, as shown in FIG. 1B, and FIGS. 2A and 2B, it is desirable that the brim portion 3 is formed such that:
(a) a lower (back) surface 3 a is convexed in a direction perpendicular to the longer axis thereof (i.e., in the second direction);
(b) the lower surface 3 a is represented by a substantially straight line in a cross section taken along a plane parallel to the longer axis (see FIGS. 1B and 2B);
(c) an upper (front) surface 3 b is concaved in the second direction which is perpendicular to the longer axis (see FIG. 2A); and
(d) the upper surface 3 b is convexed in a direction (i.e., the first direction) parallel to the longer axis (see FIG. 2B).
With this shape, the brim portion 3 is well fitted to a portion where the keyhole is formed, and accordingly, both the stability and the external appearance after the operation are improved.
Generally, if the above-described shape of the brim portion 3 is formed using dense sinter material, it may be broken or cracked during sintering. According to the embodiment, since the keyhole button 1 is formed with porous material, such a bending structure can easily be formed without causing cracks.
Further generally, if the bending structure is to be formed of the porous material, the brim portion 3 tends to be made too thick in order to retain the strength. In the embodiment, the brim portion 3 is formed to have a relatively large and slightly bent shape, and further the peripheral portion is beveled so as to prevent the brim portion 3 from becoming too thick, and to retain the strength.
In FIG. 2A, a central angle θ1 for an arc of the concave surf ace (i. e., the upper surf ace 3 b) or the convex surface (i.e., the lower surface 3 a) is preferably within a range from 30 degrees to 160 degrees. In accordance with the central angle θ1, the length of the arc is determined. If the central angle θ1 is greater than 160 degrees, the arc may be too long. Then, it would be troublesome to process the brim portion 3 to fit onto the portion around the keyhole. Therefore, it is preferable that the central angle θ1 is 160 degrees or less. If the central angle θ1 is smaller than 30 degrees, the arc may be too short, which makes it difficult to form a sufficiently curved surface. Therefore, it is preferable that the central angle θ1 is 30 degrees or greater.
As shown in FIG. 2A, it is preferable that the peripheral portion of the brim portion 3 is beveled, and that the beveled portion is formed on a surface opposite to a surface on which the shaft 2 is provided. By forming the beveled portion, the thickness of the brim portion 3 can be decreased with maintaining sufficient strength. Further, by forming the beveled portion, an area of the brim portion 3 contacting the head skin at the keyhole portion is increased. Thus, the stability of the keyhole button 1 is improved, and further, regardless of the curving shape, the strength of the brim portion 3 can be kept sufficiently. It is preferable that substantially half a thickness is cut out for beveling. The inclination angle θ2 of the beveled portion (see FIG. 2A) is preferably within a range from 40 degrees to 70 degrees. It should be noted that the brim portion 3 is formed of the porous material, the bevel angle θ2 can be adjusted corresponding to the shape of the keyhole portion during an operation.
2. Shaft Portion
The shaft portion 2 is to be inserted into the keyhole portion. Therefore, it is desirable that the shape of the shaft portion 2 can be adjusted to correspond to the keyhole portion. Generally, the shape of the keyhole is different depending on a doctor who operates. Therefore, the shaft portion 2 should be processed so as to fit in the keyhole portion during the operation.
The conventional keyhole buttons are formed such that the shape of the shaft has a predetermined cross sectional shape such as a tear-drop shape or an elliptical shape in section. Such shafts do not always fit in keyholes, and therefore, it has been difficult to provide standard products. Further, since the shaft of the conventional keyhole button is formed of dense material, it is troublesome to process the keyhole button to have a desired shape.
According to the embodiment, however, the keyhole button is made of porous material, and therefore, it can easily be processed to have a desired shape, which fits in the keyhole. Alternatively, if the shaft portion 2 is formed to be substantially cylindrical, it may be used flexibly and widely since such a shaft may fit in almost all the deficit portions. Further, if the shaft portions are formed to have a cylindrical shape, it may be possible to provide standard products.
It should be noted that the actual length should be determined depending on the thickness of the bone of each patient. However, it is generally desirable that the length of the shaft 2 is within a range from 1 mm to 20 mm. If the length is longer than 20 mm, the tip end of the shaft 2 contacts the internal dura mater. In such a case, the brim portion 3 may be spaced from the bone, and therefore the keyhole button 1 cannot be mounted stably. Further, such a shaft 2 also causes, after the operation, a problem in an appearance such that the convex portion is formed. If the length of the shaft is shorter than 1 mm, the keyhole button 1 may not be stable. It should be noted that, since the keyhole button, according to the embodiment, is made of porous material, even if the length of the shaft is longer than necessary, the length can easily be adjusted during the operation, for example, using a luer bone forceps.
The diameter R of the shaft portion 2 also varies corresponding to the size of the keyhole portion. It is generally desirable that the ratio (R/W) of the diameter R to the width W of the shorter axis of the brim portion 3 (see FIG. 1) is within a range from 0.15 to 0.3. In other words, it is desirable that the diameter R of the shaft 2 is within a range of 1 mm to 20 mm. If the diameter R is greater than 20 mm, the brim portion 3 should also be formed large. However, such a structure is not suitable for practical use. If the diameter R is smaller than 1 mm, the keyhole button may not be stably fixed at the keyhole portion.
As shown in FIGS. 1B and 2A, the shaft 2 is provided on the convex surface 3 a (i.e., the lower surface) of the brim portion 3. Since a portion at which the keyhole is slightly concaved, the convex surface 3 a, on which the shaft portion 2 is provided, can be fitted thereon and fixed stably.
As shown in FIG. 3, the shaft 2 is inserted to the keyhole such that the shaft 2 is located on the front side of the temple. If the shaft 2 is provided at the center of the brim portion 3, a part of the brim portion 3 projects toward the front of the temple, and the appearance after the operation is disfigured. Therefore, it is desirable that the shaft 2 is provided at a position C1 (see FIG. 1A) that is shifted from the center C2 of the brim portion 3 along the longer axis thereof by some extent. Specifically, it is desirable that the ratio (Lc/L) of the length Lc between a closer end of the brim portion 3 and the center C1 of the shaft 2 along the longer axis to the length L between the both ends of the arc along the longer axis is within a range from 0.3 to 0.4.
3. Manufacturing Methods
According to a first example of method of manufacturing the above-described keyhole button includes steps of:
Mixing Hydroxyapatite powder calcined at 600° C.-800° C. and methylcellulose powder in a rotary mixer;
Filling in the resultant mixture powder in a rubber mold;
Applying pressure of 1 t/cm2-2.5 t/cm2 using a hydrostatic pressing device to obtain a dried body;
Processing the dried body into the shape shown in FIGS. 1A-2B using an NC machine with taking contraction when fired; and
Firing the processed dried body for 2-5 hours, at 1100° C.-1300° C.
According to a second example of method of manufacturing the above-described keyhole button includes steps of:
Dissolving methylcellulose powder in water, and mixing the same with calcined Hydroxyapatite powder sufficiently;
Whisking the suspension (i.e., the mixture of the dissolved methylcellulose power and calcined hydroxyapatite powder) using a whisking tool;
Drying the whisked mixture in a drying machine for about one hour to form porous dried body;
Processing the dried body into the shape shown in FIGS. 1A-2B using an NC machine with taking contraction when fired; and
Firing the processed dried body for 2-5 hours, at 1100° C.-1300° C.
The present disclosure relates to the subject matter contained in Japanese Patent Application No. HEI11-298783, filed on Oct. 20, 1999, which is expressly incorporated herein by reference in its entirety.
Claims (8)
1. A keyhole button used as a supplement of a keyhole portion formed on a cranium, comprising:
a brim portion having front and back surfaces; and
a shaft portion integrally provided on the back surface of said brim portion,
wherein the front surface of said brim portion is convexed in a first direction, and concaved in a second direction which is perpendicular to said first direction.
2. The keyhole button according to claim 1 , wherein said shaft portion is substantially cylindrical.
3. The keyhole button according to claim 1 , wherein said brim portion has a rounded-rectangular shape having longer axis and shorter axis, the longer axis extending in said first direction, the shorter axis extending in said second direction.
4. The keyhole button according to claim 3 , wherein the center of said shaft portion is shifted from the center of said brim portion in said first direction.
5. The keyhole button according to claim 1 , wherein a peripheral portion on said front surface of said brim portion is beveled.
6. The keyhole button according to claim 1 , which is made of porous calcium phosphate compound.
7. The keyhole button according to claim 6 , wherein the porosity of said keyhole button is 55% or less.
8. The keyhole button according to claim 1 , which is formed of porous sinter material.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP29878399A JP3820067B2 (en) | 1999-10-20 | 1999-10-20 | Keyhole button |
JP11-298783 | 1999-10-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
US6491725B1 true US6491725B1 (en) | 2002-12-10 |
Family
ID=17864173
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/691,158 Expired - Fee Related US6491725B1 (en) | 1999-10-20 | 2000-10-19 | Keyhole button |
Country Status (2)
Country | Link |
---|---|
US (1) | US6491725B1 (en) |
JP (1) | JP3820067B2 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050090900A1 (en) * | 2003-10-22 | 2005-04-28 | Nordquist William D. | Implantable brace for a fracture and methods |
US7887587B2 (en) | 2004-06-04 | 2011-02-15 | Synthes Usa, Llc | Soft tissue spacer |
US20140172014A1 (en) * | 2012-12-17 | 2014-06-19 | Patrick J. Fitzgerald | Cranial base implant device |
WO2018098652A1 (en) * | 2016-11-30 | 2018-06-07 | 重庆博仕康科技有限公司 | Basis cranii repairing device for transsphenoidal pituitary adenoma surgery |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4188858B2 (en) * | 2003-03-06 | 2008-12-03 | 株式会社パイオラックスメディカルデバイス | Bone flap holding plate |
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US4113500A (en) | 1976-06-02 | 1978-09-12 | Asahi Kogaku Kogyo Kabushiki Kaisha | Sintered apatite body |
US4904257A (en) | 1986-03-20 | 1990-02-27 | Toa Nenryo Kogyo K. K. | Fibrous bone filler and process of producing the same |
US5458643A (en) * | 1991-03-29 | 1995-10-17 | Kyocera Corporation | Artificial intervertebral disc |
US6146422A (en) * | 1999-01-25 | 2000-11-14 | Lawson; Kevin Jon | Prosthetic nucleus replacement for surgical reconstruction of intervertebral discs and treatment method |
US6296665B1 (en) * | 2000-03-20 | 2001-10-02 | Electro-Biology, Inc. | Method and apparatus for spinal fixation |
-
1999
- 1999-10-20 JP JP29878399A patent/JP3820067B2/en not_active Expired - Fee Related
-
2000
- 2000-10-19 US US09/691,158 patent/US6491725B1/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4113500A (en) | 1976-06-02 | 1978-09-12 | Asahi Kogaku Kogyo Kabushiki Kaisha | Sintered apatite body |
US4904257A (en) | 1986-03-20 | 1990-02-27 | Toa Nenryo Kogyo K. K. | Fibrous bone filler and process of producing the same |
US5458643A (en) * | 1991-03-29 | 1995-10-17 | Kyocera Corporation | Artificial intervertebral disc |
US6146422A (en) * | 1999-01-25 | 2000-11-14 | Lawson; Kevin Jon | Prosthetic nucleus replacement for surgical reconstruction of intervertebral discs and treatment method |
US6296665B1 (en) * | 2000-03-20 | 2001-10-02 | Electro-Biology, Inc. | Method and apparatus for spinal fixation |
Non-Patent Citations (2)
Title |
---|
"Reconstrcution of Surgical Skull Defects with Hydroxylapatite Ceramic buttons and Granules" by T. Yamashima, puublished in 1988. |
T. Yamashima, "Reconstruction of Surgical Skull Defects with Hydroxylapatite Ceramic Buttons and Granules", 1988.* * |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050090900A1 (en) * | 2003-10-22 | 2005-04-28 | Nordquist William D. | Implantable brace for a fracture and methods |
US7507253B2 (en) * | 2003-10-22 | 2009-03-24 | Nordquist William D | Implantable brace for a fracture and methods |
US7887587B2 (en) | 2004-06-04 | 2011-02-15 | Synthes Usa, Llc | Soft tissue spacer |
US8945220B2 (en) | 2004-06-04 | 2015-02-03 | DePuy Synthes Products, LLC | Soft tissue spacer |
US20140172014A1 (en) * | 2012-12-17 | 2014-06-19 | Patrick J. Fitzgerald | Cranial base implant device |
US9101341B2 (en) * | 2012-12-17 | 2015-08-11 | Patrick J. Fitzgerald | Cranial base implant device |
WO2018098652A1 (en) * | 2016-11-30 | 2018-06-07 | 重庆博仕康科技有限公司 | Basis cranii repairing device for transsphenoidal pituitary adenoma surgery |
Also Published As
Publication number | Publication date |
---|---|
JP3820067B2 (en) | 2006-09-13 |
JP2001112797A (en) | 2001-04-24 |
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